According to Rovell, LeBron's new deal "easily surpasses" the 10-year, $300 million deal Kevin Durant signed with Nike in 2014.

SportsOneSource reports that James has had his own signature shoe line with Nike since his rookie season, and sales of his shoe were the highest among active players at $340 million per year, according to Forbes.

As Fortune's Daniel Roberts notes, James' deal with Nike is the latest in a series of successful business ventures. Last week, he landed a $15.8 million investment from Time Warner Cable in his media company.

Rovell also noted that Nike and James discussed possibly breaking out James' brand separately from the Nike basketball umbrella, but ultimately decided against it.